For many years it has been the almost invariable fashion to incorporate sink cabinets in newly constructed or remodeled kitchens. Such cabinets, usually constructed of wood or sometimes of metal, are conventionally provided with a top panel or counter, in which at least one sink is supported in an appropriately configured opening, and a front panel, in which are provided openings of various sizes and configurations for access to storage compartments, drawers, or spaces for drain and water supply conduits. Normally the cabinet enclosure is completed in the rear by a wall of the building, at the sides by additional panels, building walls, panels of other cabinets, or combinations of such elements, and at the base by the kitchen floor or by base panels spaced above the floor.
Sink cabinets are frequently installed in bathrooms as well, where they are sometimes referred to as "vanities" from their resemblance to dressing tables. General features of construction of bathroom sink cabinets are identical with or closely similar to those of kitchen sink cabinets. However, sink cabinets for bathrooms, normally being smaller, are more frequently prefabricated in factory or shop.
The designer or builder of sink cabinets is continually confronted with the problem of what to do with the space within the cabinet roughly defined by the inner surfaces of the top and front panels, the outer front surface of the sink, and the plane of the bottom of the sink extended to intersect the front panel. This space is normally quite small in the transverse dimension; that is, the distance between the inner surface of the front panel and the front surface of the sink. Therefore, it is not regarded as suitable to receive a conventional sliding drawer. The most frequent answer to the problem has been to do nothing at all by leaving the front panel unbroken in the area in front of the sink, sometimes applying a false drawer panel for uniformity or ornamental effect. In most such cases care is taken not to affix any sort of drawer pull, the presence of which might induce users to attempt to open the "drawer".
On the other hand, a number of expedients have been devised to make practical use of the space in question. Among these are the devices disclosed in U.S. Pat. No. 3,292,983, issued Dec. 20, 1966 to C. R. Service, and U.S. Pat. No. 4,241,963, issued Dec. 30, 1980 to C. Siedel. Each of these devices comprises a so-called drop-down drawer panel which is hinged at its bottom edge to the outer surface of the front panel of a sink cabinet for purely rotational movement to and from a position in which it closes an opening in the front panel. Affixed to the inner surface of the drawer panel is a rack or tray for storing such items as toilet articles or small kitchen implements. Mechanical stops are provided to limit the opening movement of the drawer panel.
The hinges employed in such devices are completely or partially exposed, a characteristic regarded by many as unattractive, if not unsightly. Further, the "drop-down" movement of the drawer panel is entirely unlike that of a conventional sliding drawer, which it closely resembles when closed, such movement being a surprise and therefore an annoyance until the user becomes accustomed to it through repeated operation. Also in such devices, the tray or rack is securely fastened to the drop-down panel, whereby it must be cleaned in situ or disassembled from the panel for cleaning.
Concealed hinges, and hinges which permit translational movement of the closure member which they support, are not new in themselves. Examples are disclosed in U.S. Pat. No. 1,888,345, issued Nov. 22, 1932 to E. W. Cummings, U.S. Pat. No. 2,130,663, issued Sept. 20, 1938 to L. B. Baker, U.S. Pat. No. 3,425,766, issued Feb. 4, 1969 to J. E. Crisera, German Laid-Open Patent Specification No. 23 59 467, published June 5, 1975, and German Laid-Open Specification No. 28 06 618, published Aug. 23, 1979. The hinges thus disclosed are of varying degrees of complexity and provide not only for translational movement of the closure member supported by the hinges but also for pivotal movement about axes which may be displaced by the translational movement, with the result that any point on the closure member is movable through virtually an infinite number of arcs. Further, the pivotal axes are vertically disposed, since the hinges disclosed are intended to support such closure members as doors or casement-type windows. Finally, these prior devices employ a pair of hinge arms or links which are not only dissimilar in configuration, including length, but which in all but the Baker patent are constrained to move in mutually exclusive planes.